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61.
畜禽粪污资源化利用,是农村生态环境保护工作的重点和难点,对于改善农村生态环境质量、提高农业绿色发展水平、促进农产品增产提质具有重要意义。本文为进一步了解宁夏回族自治区(简称“宁夏”)畜禽粪污资源化利用现状,在宁夏银川市、石嘴山市、吴忠市、中卫市、固原市5 市,对四大产业主导区畜禽养殖产业基本情况、全区及各市不同类型和规模的畜禽养殖粪污资源化利用现状及问题、不同养殖类型和规模的资源化主推技术及典型案例等情况进行了实地调研。结果表明:2020年,宁夏畜禽存栏总量2 046.0 万头(只),其中,奶牛57.4 万头、肉牛120.7 万头、羊596.1 万只、生猪90.0 万头、家禽1 181.8 万只。畜禽粪污产生量3 025.3 万吨,全区粪污资源化利用总量为2 961.6 万吨,综合利用率达到97.9%,规模养殖场设施配套率达99.0%,该地区畜禽粪污综合利用主要途径有肥料化利用、能源化利用、清洁再生回用等。 相似文献
62.
Among a vast number of forage trees, Vachellia karroo (Acacia karroo) remains one of the most widely distributed indigenous plant legumes in Southern Africa. The plant possesses some striking attributes, such as rapid growth rate, drought tolerance, adaptation to alkaline and acidic sterile soils, and resistance to a variety of edaphic and temperature changes. In past years V. karroo was recognised to be a major threat to rangeland productivity owing to its invasive nature. Research interest has shifted from its eradication as an unwanted plant to its utilisation as a feed resource for livestock. Extensive utilisation of V. karroo is mainly hindered by the presence of tannins and spines. Prospects to lessen the adverse effects of the anti-nutritional influences are now recognised. Vachellia karroo possesses desirable fatty acid profiles, and high protein and mineral contents that can improve animal performance. Presently, the use of V. karroo for goat production in communal areas is restricted owing to limited evidence for its nutritional value as animal feed. The present review, therefore, seeks to demonstrate the utility potential of V. karroo to improve growth performance, carcass characteristics, chevon quality, meat fatty acid profiles and as a natural anti-helminth for goats raised under an extensive system of production. 相似文献
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65.
中国东部假俭草种质资源多样性初步研究(I)
——物候期变异及其规律 总被引:1,自引:0,他引:1
对中国东部有代表性的40份假俭草[Eremochloa Ophiuroides(Munro)Hack.]种源的物候期进行了观测分析,结果表明:(1)中国东部地区假俭草种质资源的返青期、孕穗初期、盛花期、成熟期、枯萎期、青绿期均存在着不同程度的变异,其中不同种源物候期变异范围大小依次为:孕穗初期(5月29日~9月29日)>盛花期(8月28日~10月24日)>成熟期(10月9日~11月20日)>枯萎期(11月7日~12月1日)>返青期(4月18日~5月8日)。青绿期的变异范围为189~217d。(2)中国东部地区假俭草种质资源的返青期和孕穗初期随着纬度的增加而日趋提前。(3)中国东部地区假俭草种质资源的返青期、孕穗初期、盛花期、成熟期、枯萎期、青绿期间有一部分存在着显著或极显著的相关性。返青期与孕穗初期、盛花期、枯萎期呈显著的正相关,相关系数分别为0.3557、0.3429、0.3995,盛花期与枯萎期呈显著的正相关,相关系数为0.3526;孕穗初期与盛花期、成熟期呈极显著的正相关,相关系数分别为0.7834、0.4626,盛花期与成熟期呈极显著的正相关,相关系数为0.6592;而返青期与青绿期呈极显著的负相关,相关系数为-0.8019,表明假俭草的返青期愈早,青绿期愈长。 相似文献
66.
At present 18 wastewater treatment plants operateing in the Small towns of Three Gorge Areas of Chongqing Municipality, producing 132.95 tons surplus sludge everyday. As regards to the disposition of such numerous surplus sludge, the major disposition technique in these wastewater water treatment plants, i. e. , thickening and mechanical dewatering technique followed by feeding into the municipal solid waste landfill, seems to have a rather bad effect on the normal operation of the municipal solid waste landfill, due to the unstabilized sludge resulted from this technique of the sludge disposition and high moisture in the sludge, which is higher than 80%. This paper has paid some attention to this phenomenon. With respect to the small towns having the the municipal solid waste landfill, the techniques of mechanical dewatering, calcareousness stabilized etc. before feeding into the municipal solid waste landfill, seem to be feasible, while the composting and comprehensive utilization of sludge is available in the small towns which have no municipal solid waste landfills. 相似文献
67.
This paper investigates the coordinated operation of the progress planning with the resource planning when carrying out engineering projects and puts forward a method of "RSM" under the resource limit conditions. Then, the "RSM" was improved to avoid complicated calculation. This method not only reduces the calculating work by hand but saves computer's memory as well, making the time-resource optimization work more quick and convenient. 相似文献
68.
Application system generally refers to all kinds of computer information system. It aims at improving the sharing and application of the resource. The resource in application system usually means data resource. For computer management and maintenance, there are not only data resource, but also program resource and network resource. Effective management of this resource is key to ensure proper work of the application system. In this paper, the basic pattern and policy for resource management is put forward and a method to build and realize the resource layer that lies between database layer and application layer is to be found. This management layer, which skillfully connects the application system with resource and establishes good base for application and exploitation of system, is named as resource management system. 相似文献
69.
Economics.Through sampling investigation and analysis on inhabitant domestic tap water consumption situation,it is given that economic factors are the main factors influence inhatitant's water consumption.The functional relations among inhabitant's income and water consumption,water price and consumption are given. The tap water's income elasticity of demand and price elasticity of demand is analyzed, along with the fluctuating range month by month of inhabitant's water consumption.Finally ,this paper offers the reference data for planning the ability of water supply and making policies of ladder water prices. 相似文献
70.
To embed or heap industry solid wastes somewhere will occupy the earth and pollute the environment seriously. So utilizing the industry solid wastes as regeneration resource is important for sustainable development of city. Based on application and research for years in utilizing industry wastes and widely investigation, the produce status of industry solid wastes in Chongqing such as fly ash, desulfuration gypsum, blastfurnace slag and chromium slag are introduced. At the same time,this paper introduces application and research on these wastes in field of building material in Chongqing. Analyze problems and countermeasures during utilizing industry solid wastes as regeneration resource in Chongqing. As a further the prospect of utilizing industry solid wastes as regeneration resource of building material is discussed. 相似文献